1. Technical Field
The present invention relates to a driving force control system for a vehicle which banks while rounding a curve, and also relates to a saddled vehicle including such a control system.
2. Description of the Related Art
People have attempted to improve a motorcycle's running performance by controlling its driving force. When driving a motorcycle around a curve, the rider is required to twist the accelerator grip finely. For example, if the engine power increases steeply as the rider turns the accelerator suddenly, then the rear wheel will slide and other phenomena will arise. For that reason, while the motorcycle is rounding a curve, a variation in its engine power with the rider's turning the accelerator is suitably controlled with those phenomena taken into consideration.
Japanese Laid-Open Patent Publication No. 2011-185107 (which will be hereinafter referred to as “Patent Document No. 1” for convenience sake) discloses that a variation in the degree of opening of an electronically controlled throttle valve in response to the rider's accelerator turning should have a different pattern according to the motorcycle's bank angle. Patent Document No. 1 also says that if the rider is going to make a “drift run” while sliding the rear wheel intentionally, the degree of opening of the valve is increased and the engine power is increased steeply as the rider twists the accelerator grip, thereby allowing him or her to make the “drift run” easily.